The answering machine is a great convenience to telephone users. The answering machine eliminates the need for the called party to wait by the telephone to avoid missing a telephone call. In addition, the answering machine provides the calling party with the flexibility to leave a voice message for the called party if the called party is not available to answer the call. At one time the called party was required to provide special equipment to obtain answering machine capabilities. However, special equipment is no longer required if a network-based voice mail system is used.
The standard answering machine and the network-based voice mail system are alike in their basic function of recording and storing voice messages; however, the voice mail system provides additional features not available with the standard answering machine. These features include the capability to re-record a voice message; to attach an urgent status to a message, thereby cycling the urgent message to the top of the message list; to setup multiple mailboxes to receive voice messages; to allow a caller to leave a voice message when the called party's line is busy; and to continue to receive voice messages when there is a power outage.
There is one feature, however, that the network-based voice mail system has not been able to improve. Currently, the called party is not able to easily monitor a call that has been forwarded to a network-based voice mail system. A called party with a standard answering machine is able to monitor the voice message as the calling party is leaving the voice message. The answering machine answers the call and immediately plays the called party's greeting. A record message indicator, such as a beep tone, signals the calling party to leave a message. The answering machine simultaneously records the message and engages a speaker assembly. The called party is able to monitor the call without lifting the handset. If the called party elects to intercept the call during the message, the called party lifts the handset and speaks with the calling party. Once the called party lifts the handset, the answering machine stops recording and the called party can erase the partially recorded message.
Unlike the answering machine, network-based voice mail does not allow the called party to easily monitor the call as the calling party is leaving a message. One manual system that allows the calling party to monitor a call has been implemented on the Nortel DMS-100 and the Lucent 5ESS switches. This system requires the called party to detect one short ring burst in order to activate call monitoring. This short ring burst is approximately 0.5 seconds of ringing. The ringing pattern for a normal call is a repetitive two seconds ringing on, four seconds ringing off pattern. Once the short ring burst is played, the called party is required to lift the handset or go off-hook within a prescribed time limit in order to manually activate call monitoring.
There are three drawbacks of this system. The first drawback is that the called party often does not detect the short ring burst that indicates to the called party that the call monitoring service is available. Although the switch sends a short ring burst to the called party's Customer Premises Equipment (CPE), studies have shown that the short ring burst is not distinctive enough and often the called party answers the call too soon or too late.
The called party answers too soon if the called party answers the call before the call is forwarded to the voice mail system. Studies have shown that if the call is forwarded during the two-second ring, then the two-second ring is cut off. This is a normal telephony occurrence. The called party often mistakes this for the short ring burst and lifts the handset too soon. Studies have also shown that the four seconds of silence can cause the called party to believe that the prior two-second ring was the short ring burst, and so the called party lifts the handset, resulting in answering, not monitoring, the call.
The called party answers too late if the called party answers the call after the prescribed time limit. The called party is not able to monitor the call after expiration of the prescribed time limit. Studies have shown that the called party sometimes interprets the short ring burst as the “tail-end” of the regular two seconds on/four seconds off ringing pattern or, simply does not “hear” the short ring burst, so the called party does not activate call monitoring.
The second drawback is that the manual system allows the called party to monitor the call prior to the playing of the record message indicator. This raises a privacy issue because the called party is able to hear anything the caller says prior to the record message indicator, even though it is not intended as a message for the called party.
The third drawback is that a call may be monitored by a party other than the intended called party, if the call, prior to being forwarded to voicemail, had been previously forwarded. For example, consider what happens when A calls B and B's calls are being forwarded to C. If C does not answer and the call is forwarded to a network based voicemail system, then C can monitor the call and hear A's message to B.
Other systems have also attempted to solve this problem by establishing a three-way connection between the calling party, the network-based voice mail system (VMS) and the called party CPE. These systems allow the called party to monitor the calling party as if the called party were a third party. This solution has a couple of problems. One problem is that the setup time to establish the connection is too long. The calling party is asked to wait a moment before leaving a message. The wait period is required to allow the system adequate time to setup a second call to the VMS, and then join the calling party, called party, and VMS in a three-way call. Additionally this solution requires the called party to purchase three way calling and a special CPE that can automatically set up three-way calling to the VMS.
Thus, there is a need for a system, method and apparatus that allows a called party to easily monitor a call that has been forwarded to a network-based voice mail system.